title: The effect of BMP-2 on the osteoconductive properties of β-tricalcium phosphate in rat calvaria defects.
abstract: Bone formation in critical-sized calvaria defects is strongly dependent on the osteoconductive properties of grafts. It remains a matter of controversy whether biomaterials can replace autografts and whether the supplementation of biomaterials with Bone Morphogenetic Proteins (BMPs) is necessary to enhance bone formation. We examined rat calvaria critical-sized defects (5-mm-diameter) treated with β-tricalcium phosphate (TCP; Cerasorb® M), polylactic and polyglycolic acid gel (PLA/PGA; Fisiograft®) and calcium phosphate cement (CPC; Norian® CRS®), either alone or in the presence of 5 μg of BMP-2 after 45 days. Autografts and untreated defects served as controls. Bone formation was evaluated based on μCT analysis, histomorphometric analysis and fluorescence analysis. We report that TCP supported bone formation more efficiently than did autografts. Bone formation in the presence of TCP alone reached a maximal level, as BMP-2 supplementation failed to enhance bone formation. By contrast, no significant difference in bone formation was observed when PLA/PGA and CPC were compared to autografts. Moreover, the presence of BMP-2 did not substantially change the osteoconductive properties of PLA/PGA or CPC. We conclude that the osteoconductive properties of TCP are superior to those of autografts and that TCP does not require BMP-2 supplementation. Our findings also show that the decreased osteoconductive properties of PLA/PGA and CPC cannot be overcome by BMP-2 supplementation in rat calvaria defects.
authors.affiliation: Department of Oral Surgery, Medical University of Vienna, Austria.
authors.forename: Eloa R
authors.initials: ER
authors.lastname: Luvizuto
authors.forename: Stefan
authors.initials: S
authors.lastname: Tangl
authors.forename: Gerald
authors.initials: G
authors.lastname: Zanoni
authors.forename: Tetuo
authors.initials: T
authors.lastname: Okamoto
authors.forename: Celso K
authors.initials: CK
authors.lastname: Sonoda
authors.forename: Reinhard
authors.initials: R
authors.lastname: Gruber
authors.forename: Roberta
authors.initials: R
authors.lastname: Okamoto
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000627:therapeutic use*; D055396:Bone Morphogenetic Protein 2 / Q000627:therapeutic use*; D001861:Bone Regeneration / Q000187:drug effects*; D002130:Calcium Phosphates / Q000627:therapeutic use*; D019344:Lactic Acid / Q000627:therapeutic use; D011091:Polyesters; D011100:Polyglycolic Acid / Q000627:therapeutic use; D011108:Polymers / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar; D012886:Skull / Q000187:drug effects* / Q000293:injuries / Q000473:pathology
chemical_list: D001672:Biocompatible Materials; D055396:Bone Morphogenetic Protein 2; D002130:Calcium Phosphates; D011091:Polyesters; D011108:Polymers; C485817:beta-tricalcium phosphate; D011100:Polyglycolic Acid; D019344:Lactic Acid; C033616:poly(lactide)